Research ArticleOpen accessIn the abstractPoisson Quasi-Maximum Likelihood Estimator-based CUSUM Test for Integer-Valued Time SeriesSangyeol LeeThis study considers the parameter change test for integer-valued time series models based on the Poisson quasi-maximum likelihood estimates. As a change point test, we consider the score vector-based CUSUM test and show that its limiting null distribution takes the form of a function of Brownian bridges. Moreover, the residual-based CUSUM tests are considered as alternatives. For evaluation, we conduct … …Journal of Mathematics and Statistics, Vol. 15, Issue 1 · 1 Oct 2019 · 7,650 accessesView PDFCite
Research ArticleOpen accessIn the abstractA New Extension of the Lomax Distribution with Statistical Properties and Applications to Failure and Service Times Data SetsMohamed K.A. RefaieIn this work, we introduce and study a new alternative Lomax model. The maximum likelihood method is used to estimate the unknown model parameters. We show empirically the importance and wide flexibility of the new model in modeling two types of failure times data sets. The new model is much better than the gamma Lomax, exponentiated Lomax, beta Lomax and … …Journal of Mathematics and Statistics, Vol. 15, Issue 1 · 2 Feb 2019 · 7,570 accessesView PDFCite
Research ArticleOpen accessIn the abstractStatistical Modeling of Temperature Extremes Behaviour in GhanaTwumasi-Ankrah Sampson, Nyantakyi Agyei KwadwoThis paper focuses on modeling the extreme maximum temperature in Ghana using the extreme value theory. This is to inform decision-makers to help them plan appropriate risk mitigating measures to reduce the damage caused by drought. The block maxima with Generalized Extreme Value (GEV) and the General Pareto (GP) (with “all excesses” and decluster peaks) were used on 113 years … …Journal of Mathematics and Statistics, Vol. 14, Issue 1 · 10 Jan 2019 · 7,117 accessesView PDFCite
Research ArticleOpen accessIn the abstractA New Extension of the Burr Type XII DistributionMohamed K.A. RefaieIn this study, a new Burr XII distribution is defined and studied. Various structural mathematical properties of the proposed model are investigated. The maximum likelihood method is used to estimate the model parameters. We assess the performance of the MLEs of the new distribution with respect to sample size n. The assessment was based on a simulation study. The new … …Journal of Mathematics and Statistics, Vol. 14, Issue 1 · 3 Jan 2019 · 6,744 accessesView PDFCite
Research ArticleOpen accessIn the abstractThe Burr X Nadarajah Haghighi Distribution: Statistical Properties and Application to the Exceedances of Flood Peaks DataHisham A.H. Elsayed, Haitham M. YousofIn this study, new version from the Nadarajah Haghighi model is proposed. The introduced model has a failure rate function that may change in different directions. Statistical properties of the new density function are derived along with the analysis of variance, Skewness and Kurtosis. Parameter estimates are obtained by the method of maximum likelihood. Illustration of real data set was … …Journal of Mathematics and Statistics, Vol. 15, Issue 1 · 14 Jul 2019 · 7,132 accessesView PDFCite
Research ArticleOpen accessIn the abstractOn Odds Generalized Exponential-Power Lomax DistributionSalwa Mahmoud AssarA new distribution, called odds generalized exponential-power Lomax distribution is suggested for modeling lifetime data. Some structural properties of the new distribution including; quantiles, Rényi entropy, moments and distribution of order statistics are provided. The model parameters of the new distribution are estimated by the maximum likelihood method. Finally, applications to two real data sets are analyzed to illustrate the … …Journal of Mathematics and Statistics, Vol. 14, Issue 1 · 12 Jun 2018 · 7,567 accessesView PDFCite
Research ArticleOpen accessIn the abstractNew Bivariate Exponentiated Modified Weibull DistributionAbdelfattah Mustafa, Mohamed A.W. MahmoudThe new modified Weibull distribution named exponentiated modified Weibull distribution introduced by many authors. In this study, we define and study a bivariate modified Weibull distribution. Some joint probability functions and conditional probability density function are obtained. Also, joint survival function is expressed in compact form. Several statistical properties of this distribution are discussed. In the area of stress-strength models, … …Journal of Mathematics and Statistics, Vol. 13, Issue 4 · 31 Oct 2017 · 7,000 accessesView PDFCite
Research ArticleOpen accessIn the abstractRisks Ratios of Shrinkage Estimators for the Multivariate Normal MeanAbdenour Hamdaoui, Nadia MezouarWe study the estimation of the mean θ of a multivariate Gaussian random variable X∼Np(θ,σ2Ip) in ℜp, σ2 is unknown and estimated by the chi-square variable S2∼σ2χn2. In this work we are interested in studying bounds and limits of risk ratios of shrinkage estimators to the maximum likelihood estimator X, when n and p tend to infinity. We recall that … …Journal of Mathematics and Statistics, Vol. 13, Issue 2 · 3 Apr 2017 · 7,108 accessesView PDFCite
Research ArticleOpen accessIn the abstractOdds Exponential Log Logistic Distribution: Properties and EstimationRosaiah Kanaparthi, Gadde Srinivasa Rao, Kruthiventi Kalyani, Devireddy Charana Udaya SivakumarWe propose a distribution called Odds Exponential Log Logistic Distribution (OELLD), which is an odds family of distribution. Its hazard rate is an increasing and decreasing function based on the value of the parameter. Explicit expressions for the ordinary moments, L-moments, quantile, generating functions, Bonferroni Curve, Lorenz Curve, Gini's index and order statistics are derived. The parameters of the proposed … …Journal of Mathematics and Statistics, Vol. 13, Issue 1 · 25 Jan 2017 · 7,422 accessesView PDFCite
Research ArticleOpen accessIn the abstractEstimating the Claim Severity Distribution using Variable Neighborhood SearchKunjira Kingphai, Samruam ChongcharoenIn this study, Variable Neighborhood Search (VNS) is utilized to estimate the parameters of actual motor insurance claims data set and compared them obtained by the Moment Estimation Methods (MOM) and Maximum likelihood Estimation Method (MLE) which are known as a conscientious method. Then, the Kolmogorov-Smirnov test (K-S) is used to show how well the selected distribution fits the actual … …American Journal of Applied Sciences, Vol. 13, Issue 12 · 19 Dec 2016 · 7,326 accessesView PDFCite